Grand Slam Ireland, as close-knit as a shrunken jumper, cut itself into its two principal provincial parts and pitched the one against the other, brotherliness well and truly set aside, before a full house here. This was an outstanding Heineken Cup semi-final and an exceptional performance by a Leinster side who were routed in this same fixture at this same stage and in this same city three years ago.

For Munster this was a taste of their own medicine, driven to distraction and error by their determined and disciplined opponents. While they never fully ­disintegrated, their fly-half, Ronan O'Gara, had an increasingly ragged day. And as for frustration, there was a ­suggestion that Alan Quinlan towards the end may have made a little too much contact for comfort with Leo Cullen's eyes, although after the match the lock declined to accuse the Munster wing forward and Lion elect of eye-gouging. "I don't really want to comment on it at all," the Leinster captain said, instead preferring to leave the matter to the ­citing officer, John Byett.

The stage was magnificent, a world-record crowd of 82,206 for a club game, the tone set by memories of 2006, a certain fearfulness on the Leinster side that Munster might overwhelm them both in support in the stands and points on the paddock. Munster indeed won the battle on the concrete, but not on the grass.

Leinster players who had been humiliated three years ago, meanwhile, set out to provide reassurance, even if they did not last the course. Felipe Contepomi, for one, came out in determined mood, charging through his opposite number, O'Gara, and providing one of the staples of the diet with which they managed to cut Munster down to manageable size: get their Ireland fly-half.

It was a promising start by Contepomi, but after the Argentinian's first penalty attempt fell short and wide, his composure was soon further rattled when he found himself rolling about in pain on the ground as a fight broke out all around and over the top of him. He curled up in a tight ball and let the storm pass.

Good followed by bad came his way again. First, he opened the scoring with a neat drop goal after delivery from a line-out and a couple of drives by the forwards, who were standing up well to the rigours of a day out against the defending champions. Cullen was catching well above his head and Rocky Elsom was outstanding as a scythe.

The less positive follow-up to the drop goal was an injury that ended ­Contepomi's participation. He twisted a leg supporting a fine surge by Elsom – the Australian was hugely involved in both directions – and that was that for the good Argentinian doctor, a job one quarter done in the restoration of a rugby reputation.

By then the scores were level, O'Gara having kicked a penalty following a late challenge by Cian Healy. Worse still for Leinster, the prop was sent to the bin. Fortunately the first act for Contepomi's replacement, Johnny Sexton, was to line up a shot at goal. It sailed purposefully between the posts and Leinster's ­obvious hunger was rewarded.

Delivery off the top of a line-out then gave the substitute fly-half a chance to display his skills of distribution. Sexton fed Brian O'Driscoll, who moved it on to Isa Nacewa before Gordon D'Arcy was sent racing over the line for a try in the 31st minute: a move as slick as you like. Not even another penalty by O'Gara to reduce the gap to 11-6 at the interval could prevent the mood of optimism on the side regularly turned over by Munster.

Nothing dampened Blue spirits when they scored again at the start of the ­second half. O'Driscoll was involved twice, starting the counter-attack, pausing while the tight forwards drove up one touchline, before releasing Luke Fitzgerald down the other. The finish by one of the 10 Lions involved in this encounter was exemplary, his side-step reducing his finishing speed not a jot. He soon limped off, but with nothing more serious than a cramp, according to the Leinster coach, Michael Cheika.

Inevitably, the Munster surge began, albeit tinged with a certain carelessness, a nascent desperation. O'Gara, for ­example, was starting to show loose threads: kicks off target, passes inaccurately given, a fumble on the touchline.

Still, the collective will drove his team on, only for the ball to be stripped from the forwards twice in the Leinster 22. The desperation was growing and reached full bloom when O'Gara threw a pass to Paul O'Connell, only for O'Driscoll to intercept and run the length of the field. It was a brilliant performance by O'Driscoll, who had suffered the torture of 2006, and by Elsom, who had not. A new Leinster have arisen, and new finalists are going to Murrayfield.

As for the defeated side, well, this was chastening. They have lost before, but never by a margin such as this with so much at stake, and never at the hands of their brothers. A few ghosts may have entered the house of Munster and it is their turn to be haunted by what ­happened one day in Dublin.